Risk factors for the development of carbapenem-resistant Klebsiella pneumoniae infections in critically ill patients

Introduction

We sought to study the characteristics and outcomes of ICU patients with carbapenem-resistant (CRKp) and carbapenem-sensitive (CSKp) K. pneumoniae infections.

Methods

A retrospective cohort of patients requiring ICU treatment. The study was conducted in an eight-bed ICU between January 2006 and September 2009.

Results

During the study period, 104 patients were diagnosed with K. pneumoniae infection. The mean age of patients was 66.3 ± 14.3 years. Fifty-one (49%) were males. The mean APACHE II score was 17.9 ± 6.9. The median duration of hospital stay until the infection was 28 days. Fortyeight patients (46.2%) had bacteremia, 27 (30%) urinary tract infections, 15 (14.4%) pneumonia, seven (6.7%) peritonitis and seven (6.7%) skin and soft tissue infections. Fifty-eight (56.9%) and 39 (39%) patients had previous and concurrent infections, respectively. Seventy-six patients (73.1%) died. The univariate analysis showed that prior hospitalization (P = 0.049), dialysis (P = 0.034), and history of urologic neoplasia (P = 0.041) were associated with the development of carbapenem-resistant infections. No independent risk factors were found in the multivariate analysis. APACHE II score (P = 0.003), need for dialysis (P = 0.034), shock prior and after the infection (P = 0.006 and P < 0.001, respectively), respiratory distress prior and after the infection (P = 0.021 and P = 0.032, respectively), multiorgan failure prior and after the infection (P = 0.02 and P = 0.003, respectively), treatment failure (P < 0.001), and acidosis after the development of infection (P = 0.003) were associated with death in the univariate analysis. Shock after the infection (P = 0.016) and treatment failure (P = 0.001) were independent predictors of mortality in the multivariate analysis. No difference in mortality was found between patients with CRKp and CSKp isolates.

Conclusions

Infection due to K. pneumoniae in the ICU is associated with high mortality. Infection treatment and hemodynamic support of the patient may be important determinants of the clinical course in critically ill patients with such infections.